Apparatus fob recording vibrations



Feb. 19, 1935. v F. TOEWE 1,992,134

APPARATUS FOR RECORDING VIBRATIONS Filed June 1, 1932 2 Sheets-Sheet 1 JrHJen/or 7,7 Tiewe,

Feb. 19,1935. I I F. CTOEWE APPARATUS FOR RECORDING vmnnmns Filed June 1, 195g 2 Sheets$heet 2 Patented Feb. 19, 1935 v UNITED STATES PATENT OFFICE- Fritz 'Ioewe, Villingen-Scliwanwald, Germany, assignor to Kienzle Taxameterund Apparate A;-G., Villingcn-Schwarzwald, Germany, a corporation of Germany Application June 1, 1932, Serial No. 614,765

In G

3 Claims.

My invention relates to improvements in apparatus for recording vibrations, such as are used for example on motor vehicles-for showing the periods of time during which the vehicle was in operation, .and which comprise a rockingly mounted weighted body connected with a stylus recording the vibrations on a record disk. The object I of the improvements is to provide an apparatus of this type by means of which exceedingly fine vibrations may be measured, such as are produced for example when the motor of the vehicle is in operation and disconnected from the driving mechanism. With this object in view my invention consists in providing mechanism intermediate the said weighted body and the stylus for enlarging the amplitude of the vibrations, so that even very fine vibrations are distinctly recorded on the recording surface.

Other objects of the improvements will appear from the following description.

For the purpose of explaining the invention an example embodying the same has been shown in the accompanying drawings in which the same reference characters have been used in all the views to indicate corresponding parts. In said drawings,

Fig. 1 is an elevation of the apparatus showing the casing enclosing the operative parts open,

Fig. 2 is an elevation of the apparatus showing the operative parts in a different position,

Fig. 3 is an elevation partly in section taken on the line 3--3 of Fig. 1, and

Fig. 4 is an elevation similar to the one illustrated in Fig. 1 and showing a modification.

In the example shown in the drawings the apparatus comprises a casing 35 having a hinged lid 36. On a pivot bolt 2 fixed to the rear wall of the casing35 a lever 1 carrying a weighted body 3 is rockingly mounted, the said weighted body being suspended from a coiled spring 4 normally holding the same in median position between stops 5 and 6 secured to the rear wall of the casing. On the lever 1 a pin 7 is rotatably' mounted which carries a bell crank lever 8, 9 made from highly elastic spring steel. To the rear wall of the casing 35 a plate 11 is secured by means of a screw 12 passed through a longitudinal slot of the said plate, and the plate is formed with a forwardly directed slotted arm 10 engaged by the short arm 9 of the bell crank lever 8, 9. The lever 1 is formed with -a cutout portion 13 through which the plate 11 is visible. I

The upwardly directed long arm 8 of the bell crank lever is bent forwardly at its top end, as

ermany October 9, 1931 is shown at 14, and the said forwardly directed end engages in a longitudinal slot 15 of a bell' crank lever 16 mounted on a pivot bolt 1'7 secured to the rear wall of the casing 35. At its free end the bell crank lever 16 carries a stylus 17' 5 which is directed forwardly therefrom and into position for engaging a record disk 18 mounted on the inner face of the lid 36 and rotated by a clock work disposed on the lid 36. The vibrations imparted to the bell crank lever 16 are limited 10 by stops 19 and 20. In the normal position the said bell crank lever is in median position between the stops 19 and 20, as is shown in Fig. 1..

In the operation of the apparatus the weighted body 1, 3 vibrates between the stops 5 and 6, and 15 the said vibrations are transmitted to the bell crank lever 8, 9, the arm 9 of the said bell crank lever sliding in the slotted arm 10 of the plate 11. The slotted arm 10 is fixed in position, while the'pivot bolt '7 takes part in the oscillating movement of the weighted body 1, 3, and therefore the bell crank lever 8, 9 is vibrated so that the longer arm 8 is rocked to and fro. By reason of the difference of the lengths of the arms 8 and 9, the amplitude of the vibrations of the top end 25 of the arm 8 is considerably increased as compared to the amplitude of the weighted body 1,

3. The said rocking movement of the arm 8 is transmitted to the lever 16 by the arm 14 engaging in the slot 15. By reason of the elasticity 30 of the bell crank lever 8, 9the lever 16 smoothly engages the stops 19 and 20 which limit the vibrationsthereof. The oscillating movement of the lever 16 imparts corresponding oscillating movements to the stylus 17' by means of which 35 the said oscillations are recorded on the disk 18.

While the vehicle or other device on which the apparatus is mounted is at rest the record takes the form of a line 22, and when vibrations are recorded the record takes the form of a surface 21.

By constructing the bell crank lever 8, 9 from highly elastic steel the energy of the oscillation transmitted from the weighted body to the spring 8, 9 is not annihilated, but it is stored in the bell crank lever. This is one of the reasons of the high sensitiveness of the apparatus. 7

In my improved apparatus even very small oscillations of the weighted body are surely and distinctly recorded and an exact contour of the record is produced. Thus the apparatus records also weak vibrations such as are produced in a vehicle which is at rest while its motor is in op-' eration and disconnected from the driving mechanism. The lever 16 on whichjhe stylus is v mounted is pressed on its stops 19 or 20 only with the small force exerted by the spring lever 8, 9, while heavy blows are taken up by the stops 5 and 6 acting on the weighted body.

By shifting the plate 11 and the slotted arm 10 thereof longitudinally of the arm 9 or the elastic bell crank lever 8, 9 the gear ration of the mechanism transmitting the vibrations from the weighted body to the stylus may be varied within broad limits and in a very simple way.

My improved vibration meter may be used wherever it is desired to record very fine oscillations, and it may be used in connection with stationary or moving objects. r

In the construction of the apparatus illustrated in Figs. 1 to 3 the record is produced on the rec- 0rd disk 18 along a concentric line, and therefore the record disk can be used only during a single rotary movement. As shown in Fig. l the record disk contains twenty-four scale marks, according to the twenty-four hours of the day.

In Fig. 4 I have shown a modification in which the record disk can be used for a longer time, by constructing the operating mechanism of the stylus so that the stylus moves through a spiral line.

As shown in the said figure, the stylus 17' is secured to an arm 25 fixed to the lever 16, and an extension 16 of the lever 16 is jointed to the free end of a lever 26 rockingly mounted on a pivot bolt 27 fixed to the rear wall of the casing 35. A pin 18' extending rearwardly from the lever 26 engages in a spiral cam slot 29 made in the body of a gear wheel 30 rotatably mounted on the rear wall of the casing 35. .The clock work mounted on the lid 36 is provided with a pinion 33 secured to an arbor 31, and the pinion is adapted for engagement with the gear wheel 30.

When the lid 36 is rocked upwardly for closing the casing the pinion 33 and gear wheel 30 get into engagement with each other, so that the gear wheel 30 and the cam slot 29 thereof are slowly rotated, the gear ratio being such that after a complete rotation of the record disk 18 the levers 26 and 16 have been moved inwardly so far that the next record is drawn on the disk 18 internally of the record first'made, the record taking the form of a spiral line 3'7. The displacement of the lever 16 is possible by reason of the engagement of the arm 14 in the longitudinal slot 15.

I claim:

1. An apparatus for recording vibrations, comprising a movably mounted weighted body, a rockingly mounted lever carrying a stylus, stops limiting the movements of said lever, a bell crank lever having elastic arms rockingly mounted on said weighted body and engaging with one arm said lever, and a relatively fixed member engaging the other arm of said bell crank lever.

2. An apparatus for recording vibrations, comprising a movably mounted weighted body, a slotted lever carrying a stylus, stops for limiting the movements of said lever, a bell crank lever having elastic arms and rockingly mounted on said weighted body, one of the arms of said bell crank lever engaging the slot of said slotted lever, and a relatively fixed member loosely engaging the other arm of said bell crank lever.

3. An apparatus for recording vibrations, comprising a rockingly mounted weighted body, a lever carrying a stylus, a bell crank lever mounted on said weighted body and engaging said lever carrying the stylus with one arm, and a relatively fixed member engaging the other arm of the said bell crank lever and adjustable longitudinally of said armr FRITZ TOEWE. 

